为何TPanel不是Controls? ( 积分: 50 )

H

houtor

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2007-02-08

• #1

有Form1加上几个TSpeedButton和TPanel控件,代码如下:
for i := 0 to Form1.ControlCount-1 do begin
if Form1.Controls is TSpeedButton then
if TSpeedButton(Form1.Controls).Visible then
TSpeedButton(Form1.Controls).Visible:=False
else TSpeedButton(Form1.Controls).Visible:=True
else if Form1.Controls is TPanel then
if TPanel(Form1.Controls).Visible then
TPanel(Form1.Controls).Visible:=False
else TPanel(Form1.Controls).Visible:=True
end;
TSpeedButton可以,但if Form1.Controls is TPanel then下的根本不运行,难道TPanel控件不是Controls类型的吗(Form1.Controls is TPanel = false呀),如何改呀?

 

W

wr960204

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2007-02-08

• #2

大概你没有引用TPanel所在的ExtCtrls单元吧。

 

3

3868474

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2007-02-08

• #3

Tpanel肯定是TControl的子类, 也许那几个Panel的parent不是Form1吧,另外这样好象更简单
for i := 0 to Form1.ControlCount-1 do
if Form1.Controls is TSpeedButton then
TSpeedButton(Form1.Controls).Visible:= not TSpeedButton(Form1.Controls).Visible
else if Form1.Controls is TPanel then
TPanel(Form1.Controls).Visible:= TPanel(Form1.Controls).Visible;

 

3

3868474

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2007-02-08

• #4

Tpanel肯定是TControl的子类, 也许那几个Panel的parent不是Form1吧,另外这样好象更简单
for i := 0 to Form1.ControlCount-1 do
if Form1.Controls is TSpeedButton then
TSpeedButton(Form1.Controls).Visible:= not TSpeedButton(Form1.Controls).Visible
else if Form1.Controls is TPanel then
TPanel(Form1.Controls).Visible:= not TPanel(Form1.Controls).Visible;

 

D

dyxfkj

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2007-02-08

• #5

楼上兄弟说得没错：

我测了一下

procedure TForm1.Button1Click(Sender: TObject);
var
i: Integer;
begin

for i := 0 to Form1.ControlCount-1 do
if Form1.Controls is TSpeedButton then
TSpeedButton(Form1.Controls).Visible:= not TSpeedButton(Form1.Controls).Visible
else if Form1.Controls is TPanel then
TPanel(Form1.Controls).Visible:= not TPanel(Form1.Controls).Visible;
end;

 

L

lcmlhs

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2007-02-08

• #6

帮顶，学习一下！

 

H

houtor

Unregistered / Unconfirmed

GUEST, unregistred user!

• 2007-02-09

• #7

多谢了,是我搞晕了头脑.